Turning Archive 2007

Subject:

Machinist knurl for spiraling/texturing

Ken Grunke from SW WI>Tonight was hectic for me, I had planned to join the chat and share my knurling wheel spiraling and texturing tool. I'm visiting at my sister's dairy farm for a week, a few hours from home, and brought a little Carbatech lathe with me which is set up in a mobile home trailer about 15 yards from the house.

Between a little turning, showing Sis how to bake bread in the kitchen, hopping back out to the trailer to take a couple pics, then running back in to upload them and finding out I had to install Java to get in the chat, I finally got the chat going and ready to log in at 10:30 pm Eastern. I decided not to bother since everyone would likely be signing out.

So here's the tool, a machinist's knurling wheel with fine-pitched angled teeth, mounted on a length of 1/2" keystock for a handle. The Sorby and Serious tools use ball bearings for each wheel and are much bigger, but this wheel spins direct on a little 1/4" shoulder bolt and works just fine as long as you keep the speed down. I set the toolrest just a bit over center, and start the wheel spinning by pressing it's face against the work first, then angle it down just a bit until the top edge starts cutting.

Use a light touch and practice on scrap to get the feel of using the tool. Machinist knurls are available in a wide variety of diameters and pitches, this one of mine is one of the smallest available at 3/4" diam. I think Enco has them and mscdirect.com as well, or any well-stocked machinist supply outfit.
In my opinion a straight-toothed wheel of coarser pitch and larger diameter would be more useful. When I get one, it will be mounted on a round shaft with a bracket just like the Sorby and Serious tools.

Here's a better shot of the spiraling itelf, on a piece of spalted maple from Sis's firewood pile:

And a closer shot--it takes a bit of finesse and some luck to get a nice looking spiral and harder woods give best results: